[ot] Fix EarlGrey GPIO DIRECT_OUT/DIRECT_OE readback#329
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moidx
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… readback
ot_gpio_eg_read() returned s->regs[reg] for DIRECT_OUT and DIRECT_OE.
Those register slots are only updated on a direct write, but firmware
that drives outputs through MASKED_OUT_{LOWER,UPPER} /
MASKED_OE_{LOWER,UPPER} updates s->data_out / s->data_oe and never the
DIRECT_* register slots. As a result a value set via a masked write was
not observable through a DIRECT_OUT read, which read back as 0.
DIRECT_OUT and the MASKED_OUT registers are alternate views of the same
output data register on real hardware (likewise DIRECT_OE and MASKED_OE),
so return the live s->data_out / s->data_oe instead.
Signed-off-by: Miguel Osorio <miguelosorio@google.com>
jwnrt
approved these changes
Jun 1, 2026
luismarques
approved these changes
Jun 1, 2026
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ot_gpio_eg_read() returned s->regs[reg] for DIRECT_OUT and DIRECT_OE. Those register slots are only updated on a direct write, but firmware that drives outputs through MASKED_OUT_{LOWER,UPPER} / MASKED_OE_{LOWER,UPPER} updates s->data_out / s->data_oe and never the DIRECT_* register slots. As a result a value set via a masked write was not observable through a DIRECT_OUT read, which read back as 0.
DIRECT_OUT and the MASKED_OUT registers are alternate views of the same output data register on real hardware (likewise DIRECT_OE and MASKED_OE), so return the live s->data_out / s->data_oe instead.